A caveat: a very recent study refined that premise, demonstrating that only when too many choices induce anxiety is this really an issue. The main driving factor appears to be time as you say... which makes perfect sense. If I have days to decide, 20 choices is great. If I have mere minutes, not so much. But I'm in alignment anyway. 60 "varieties" of toothpaste on my grocer's shelf is about 50 too many IMO.